Dental OSCE (Objective Structured Clinical Examination) Practice Exam

When should non-rigid connectors be used in fixed partial dentures (FPDs)?

1. On long spans

2. When preps are not parallel

3. In aesthetic areas

4. For all cases

The correct answer is: When preps are not parallel

Non-rigid connectors are specifically designed for use in situations where the abutment teeth or the preparations for them are not parallel. In fixed partial dentures (FPDs), non-rigid connectors allow for a degree of movement between the components, accommodating the natural movement of teeth and reducing stress on the connectors and the surrounding tooth structure. This is particularly important when the teeth being connected do not align perfectly, which can happen due to variations in the tooth anatomy, prior restorations, or the angulation of the available teeth. While long spans (the option related to the first choice) may require strong connectors, non-rigid connectors are not a blanket solution for all long-span situations and may in fact be better suited for more complex configurations. Aesthetic areas, while important considerations, do not inherently dictate the need for non-rigid connectors, as they primarily address the functionality and movement tolerances of the FPD. Regarding the last option, imposing non-rigid connectors on all cases would not be practical or necessary, as many situations could be effectively treated with rigid connectors without the added complexity. Thus, employing non-rigid connectors in cases of non-parallel preparations ensures the longevity and functionality of the fixed partial denture while accommodating the natural variability in tooth positions